As networks and computers have been able to deliver information faster, users no have begun to expect instantaneous information and information available from anywhere in the world. The vast amount of information available has created an overload of information for the user.
Internet search tools and search engines allow users to find information by searching for keywords throughout an index of millions of documents posted on websites. However, a problem with the search engines is the inability to receive updated information on specific pages. A user may frequently access the information on web pages to see if changes have occurred, but this is time consuming. Accessing information is tedious, particularly when information contained in a large database and large searches must be conducted.
Software tools have been developed to automate the task of detecting updates to information on web pages and within databases. These tools allow users to specify keywords which are periodically searched for in a news database. Some of these tools send news articles containing the specified keywords to the user by electronic mail (e-mail).
These automated software tools are sometimes known as “netbots”, a network robot which automatically performs some task for a user. Netbots allow the users to manage the information within databases and reduce the amount of information that the user must read. Filtering of the information is critical to making good use of the overwhelming amount of information available to the user.
Change detection tools allow users to register a document or web page on the Internet and be notified when any change to that document occurs. The user registers a document by specifying the URL of the document and providing the user's e-mail address. The change detection tool stores a local copy of the document together with the user's e-mail address. Periodically (for example daily or weekly), the change detection tool access the source document specified by the URL and compares the retrieved source document to the local saved copy of the document. If a difference between the two copies is detected, a message is sent to the user's e-mail address notifying the user of the change in the document. These document change tools may store an actual copy of the entire document on the tools website for comparison. However, such tools are inefficient for retrieving updated information within a database, for example, an auction site. Because of the large amount of data within these sites, a user may be notified too often or with too much information for the updates to be useful. Often the user is notified of many insignificant changes and frequent e-mail notices of minor irrelevant changes become irritating to the user. In addition, such URL reminders notify the user only that a change has taken place and do not highlight the changes or indicate the changes to the user. Thus, the user must re-read the entire document to determine what has changed.